232 research outputs found

    Statistical Properties for Coherence Estimators From Evolutionary Spectra

    No full text

    A Statistical Analysis of Morse Wavelet Coherence

    No full text
    Published versio

    A Statistical Study of Temporally Smoothed Wavelet Coherence

    No full text
    Published versio

    Analysis of point based image registration errors with applications in single molecule microscopy

    No full text
    We present an asymptotic treatment of errors involved in point-based image registration where control point (CP) localization is subject to heteroscedastic noise; a suitable model for image registration in fluorescence microscopy. Assuming an affine transform, CPs are used to solve a multivariate regression problem. With measurement errors existing for both sets of CPs this is an errors-in-variable problem and linear least squares is inappropriate; the correct method being generalized least squares. To allow for point dependent errors the equivalence of a generalized maximum likelihood and heteroscedastic generalized least squares model is achieved allowing previously published asymptotic results to be extended to image registration. For a particularly useful model of heteroscedastic noise where covariance matrices are scalar multiples of a known matrix (including the case where covariance matrices are multiples of the identity) we provide closed form solutions to estimators and derive their distribution. We consider the target registration error (TRE) and define a new measure called the localization registration error (LRE) believed to be useful, especially in microscopy registration experiments. Assuming Gaussianity of the CP localization errors, it is shown that the asymptotic distribution for the TRE and LRE are themselves Gaussian and the parameterized distributions are derived. Results are successfully applied to registration in single molecule microscopy to derive the key dependence of the TRE and LRE variance on the number of CPs and their associated photon counts. Simulations show asymptotic results are robust for low CP numbers and non-Gaussianity. The method presented here is shown to outperform GLS on real imaging data.</p

    Shear bond strength of ceramic fused to CAD-CAM milled alloys

    Get PDF
    This study evaluated the metal ceramic bond strength of cast Ni-Cr, cast Co-Cr, sintered Co-Cr and milled Co-Cr alloys to ceramic through two application procedures including the ceramic layering technique and ceramic pressed-on technique. Ceramic materials (Ø 8 mm, 1.5 mm thickness) were veneered by either the layering or pressed-on technique to cast Ni-Cr, cast Co-Cr, sintered Co-Cr and hard milled Co-Cr alloy disc (12 × 12 × 0.5 mm) (n=15). All specimens were treated with a thermal cycle process for 500 cycles at the temperature between 5 °C and 55 °C with immerse time of 30 seconds and 5 seconds for specimen transfer. The shear bond strength was determined on a universal testing machine at a crosshead speed of 0.5 mm/min. The de-bonding surfaces were examined under visual inspection and SEM. The metal ceramic interface of specimens for each group was examined in SEM and EDS. The means of bond strength were compared using two-way ANOVA followed by post-hoc Tukey HSD multiple comparison test to determine for statistically significant difference at 95% level of confidence. The Weibull analysis was used for determination survival probability of shear bond strength. The bond strength of ceramic to sintered Co-Cr alloys was higher than that to others metal alloys. The metal-ceramic mean bond strength was significantly higher for the ceramic pressed-on technique than that of the ceramic layering technique for all tested alloys (p<0.05). Weibull analysis of the shear bond strength indicated that the sintered Co-Cr alloys veneered with heat pressed ceramic provided the highest characteristic strength of metal ceramic bond. The sintered Co-Cr alloys significantly contributed the appropriate bond strength for metal ceramic. Ceramic pressed-on was a reliable technique to enhance bond strength for fabrication the metal ceramic restoration

    Devising a fairer method for adjusting target scores in interrupted one-day international cricket

    Get PDF
    One-day international cricket matches face the problem of weather inter- ruption. In such circumstances, a so-called rain rule is used to decide the outcome. A variety of approaches for constructing such rules has been pro- posed, with the Duckworth-Lewis method being preferred in the sport. There are a number of issues to consider in reasoning about the e ↵ ectiveness of a rain rule, notably accuracy (does the rule make the right decision?) and fairness (are both teams treated equally?). We develop an approach that is a hybrid of resource-based and so-called probability-preserving approaches and provide empirical evidence that this hybrid method is superior in terms of fairness while competitive in terms of accuracy

    Climate Change and National Laws across Commonwealth Countries

    Get PDF
    This paper furthers the Commonwealth agenda on climate action by exploring the kinds of ‘practical and swift action’ that might be taken through national legal frameworks to implement the Paris Agreement. The paper reviews national laws of Commonwealth member countries as they currently apply to and intersect with climate change. The paper investigates legal measures that relate directly to implement climate change policy, including climate change legislation and regulatory instruments such as emissions trading schemes and energy efficiency measures. It also considers indirect legal measures that can provide ‘co-benefits’ in relation to climate change policy, such as waste legislation and air quality measures. The paper presents examples of these different kinds of climate intersections in different Commonwealth legal systems, highlighting examples of what has worked well and what has not worked well to date, within different legal, economic and political cultures, and in different geographies and climates

    Cortical State Fluctuations during Sensory Decision Making

    Get PDF
    In many behavioral tasks, cortex enters a desynchronized state where low-frequency fluctuations in population activity are suppressed. The precise behavioral correlates of desynchronization and its global organization are unclear. One hypothesis holds that desynchronization enhances stimulus coding in the relevant sensory cortex. Another hypothesis holds that desynchronization reflects global arousal, such as task engagement. Here, we trained mice on tasks where task engagement could be distinguished from sensory accuracy. Using widefield calcium imaging, we found that performance-related desynchronization was global and correlated better with engagement than with accuracy. Consistent with this link between desynchronization and engagement, rewards had a long-lasting desynchronizing effect. To determine whether engagement-related state changes depended on the relevant sensory modality, we trained mice on visual and auditory tasks and found that in both cases desynchronization was global, including regions such as somatomotor cortex. We conclude that variations in low-frequency fluctuations are predominately global and related to task engagement

    Laparoscopic repair of a right-sided Bochdalek hernia with sigmoid in an adult:A case report

    Get PDF
    The Bochdalek hernia is a rare congenital defect in the posterolateral diaphragm, often presented at pediatric age with symptoms such as respiratory complaints due to mechanical obstruction of the intestines. Organs as the kidney, spleen and pancreas tend to herniate usually through the left hemidiaphragm. We present a case of a right sided Bochdalek hernia with an obstructed sigmoid colon in an adult. During my stay I had faith in the surgeon and nurses. They informed me well throughout the whole process and the surgeon was sincerely involved. I felt comfortable during my stay in the hospital and my recovery was quick
    corecore